Wheelchairs have long been used by disabled persons for aiding mobility. They comprise a rigid frame, which may or may not fold for storage, on which are mounted a pair of large wheels at one end for pushing by the occupant and a set of steerable caster wheels at the other end which enable the chair to be turned and maneuvered. In all observable cases, the wheels are mounted directly on the rigid frame and thus jolts caused by any unevenness in the traveled surface are transferred directly to the seat occupied by the user of the chair. Persons confined to wheelchairs experience considerable pain and discomfort from these jolts.